Japanese patent publication JP 5050346A discloses a machine for the separative machining of plate-shaped workpieces by means of a laser beam, in the form of a combined laser and punching machine. The machine disclosed by JP 5050346A implements hybrid movement control, in which the workpiece is moved in a first direction (X direction) and the machining head is moved in a second direction (Y direction). The displacement of a workpiece bearing, to prevent damage by the machining beam, is interrupted in the movement range of the machining head. Therefore, in the workpiece bearing, a gap extends in the Y direction between two workpiece bearing faces or workpiece bearings. The machining beam that has passed through the workpiece, and any slag or cutting scraps formed, are discharged through the gap. The machining beam can be a laser beam, though the use of some other type of high-energy beam, for example in the form of a plasma arc or a water jet, is also possible.
In the case of such a machine, efforts are focused on keeping the gap required for the passage of the machining beam as small as possible in order to ensure the best possible workpiece support. If such a (laser) processing machine is to have an additional axis for movement of the machining head in an X direction, it is however necessary for the gap to have a minimum width that corresponds at least to the movement range of the machining head in the X direction.
Regardless of the width of the gap, it is potentially possible for collisions with downwardly hanging workpiece parts to occur at those side edges of the workpiece bearings that delimit the gap. For example, during the machining or separating cutting, a situation may arise in which a cut off workpiece part or individual contour sections of the workpiece part are supported only by one of the workpiece bearings. In particular, in the case of a separation cut, this can, owing to the action of the cutting gas pressure on the workpiece part that has been cut off, lead to restrictions in process reliability, because the workpiece part that has been cut off can tilt into the gap. Furthermore, in the case of long, thin workpiece parts, a situation may arise in which the workpiece part bends into the gap.